Republicans risk losing their 54-46 Senate majority with several vulnerable incumbents up for re-election this year. Republican analysts and pollsters have predicted dire consequences for Republican legislators if Trump wins the GOP nomination, stifling their re-election chances.

Republican senators including McConnell have lashed out privately against 2016 candidate John Kasich's continued presence, arguing his "intransigence" is blocking Republicans from uniting behind an anti-Trump,” according to the Times.

Trump has won three of the four first presidential primaries and leads in most states voting on Super Tuesday, which could virtually cement his lead.